diff mbox series

[1/2] md: factor out a helper exceed_read_errors() to check read_errors

Message ID 20231204070327.3150356-2-linan666@huaweicloud.com (mailing list archive)
State Superseded, archived
Delegated to: Song Liu
Headers show
Series support read error check in raid1 | expand

Commit Message

Li Nan Dec. 4, 2023, 7:03 a.m. UTC 
From: Li Nan <linan122@huawei.com>

Move check_decay_read_errors() to raid1-10.c and factor out a helper
exceed_read_errors() to check if read_errors exceeds the limit, so that
raid1 can also use it. There are no functional changes.

Signed-off-by: Li Nan <linan122@huawei.com>
---
 drivers/md/raid1-10.c | 54 +++++++++++++++++++++++++++++++++++++++++++
 drivers/md/raid10.c   | 47 +------------------------------------
 2 files changed, 55 insertions(+), 46 deletions(-)

Comments

Song Liu Dec. 8, 2023, 6:38 p.m. UTC | #1 
On Sun, Dec 3, 2023 at 11:04 PM <linan666@huaweicloud.com> wrote:
>
> From: Li Nan <linan122@huawei.com>
>
> Move check_decay_read_errors() to raid1-10.c and factor out a helper
> exceed_read_errors() to check if read_errors exceeds the limit, so that
> raid1 can also use it. There are no functional changes.
>
> Signed-off-by: Li Nan <linan122@huawei.com>
[...]
> +static inline bool exceed_read_errors(struct mddev *mddev, struct md_rdev *rdev)
> +{
> +       int max_read_errors = atomic_read(&mddev->max_corr_read_errors);
> +       int read_errors;
> +
> +       check_decay_read_errors(mddev, rdev);
> +       read_errors =  atomic_inc_return(&rdev->read_errors);
> +       if (read_errors > max_read_errors) {
> +               pr_notice("md:%s: %pg: Raid device exceeded read_error threshold [cur %d:max %d]\n",
> +                         mdname(mddev), rdev->bdev, read_errors, max_read_errors);
> +               pr_notice("md:%s: %pg: Failing raid device\n",
> +                         mdname(mddev), rdev->bdev);

This changed the print message from "md/raid10:" to "md:". We should
try to avoid
such changes. How about we do something like the following?

Thanks,
Song

diff --git i/drivers/md/raid1-10.c w/drivers/md/raid1-10.c
index 3f22edec70e7..6c0ef0fe6ba7 100644
--- i/drivers/md/raid1-10.c
+++ w/drivers/md/raid1-10.c
@@ -173,3 +173,10 @@ static inline void
raid1_prepare_flush_writes(struct bitmap *bitmap)
        else
                md_bitmap_unplug(bitmap);
 }
+
+static inline bool exceed_read_errors(struct mddev *mddev, struct
md_rdev *rdev)
+{
+       pr_notice("md/" RAID_1_10_NAME ":%s: %pg: Raid device ...\n",
+                 ...);
+       ...
+}
diff --git i/drivers/md/raid1.c w/drivers/md/raid1.c
index 9348f1709512..412e98d02a05 100644
--- i/drivers/md/raid1.c
+++ w/drivers/md/raid1.c
@@ -49,6 +49,7 @@ static void lower_barrier(struct r1conf *conf,
sector_t sector_nr);
 #define raid1_log(md, fmt, args...)                            \
        do { if ((md)->queue) blk_add_trace_msg((md)->queue, "raid1 "
fmt, ##args); } while (0)

+#define RAID_1_10_NAME "raid1"
 #include "raid1-10.c"

 #define START(node) ((node)->start)
diff --git i/drivers/md/raid10.c w/drivers/md/raid10.c
index 375c11d6159f..a1531b5f15e3 100644
--- i/drivers/md/raid10.c
+++ w/drivers/md/raid10.c
@@ -77,6 +77,8 @@ static void end_reshape(struct r10conf *conf);
 #define raid10_log(md, fmt, args...)                           \
        do { if ((md)->queue) blk_add_trace_msg((md)->queue, "raid10 "
fmt, ##args); } while (0)

+#define RAID_1_10_NAME "raid10"
+
 #include "raid1-10.c"

 #define NULL_CMD

[...]
Li Nan Dec. 11, 2023, 7:59 a.m. UTC | #2 
在 2023/12/9 2:38, Song Liu 写道:
> On Sun, Dec 3, 2023 at 11:04 PM <linan666@huaweicloud.com> wrote:
>>
>> From: Li Nan <linan122@huawei.com>
>>
>> Move check_decay_read_errors() to raid1-10.c and factor out a helper
>> exceed_read_errors() to check if read_errors exceeds the limit, so that
>> raid1 can also use it. There are no functional changes.
>>
>> Signed-off-by: Li Nan <linan122@huawei.com>
> [...]
>> +static inline bool exceed_read_errors(struct mddev *mddev, struct md_rdev *rdev)
>> +{
>> +       int max_read_errors = atomic_read(&mddev->max_corr_read_errors);
>> +       int read_errors;
>> +
>> +       check_decay_read_errors(mddev, rdev);
>> +       read_errors =  atomic_inc_return(&rdev->read_errors);
>> +       if (read_errors > max_read_errors) {
>> +               pr_notice("md:%s: %pg: Raid device exceeded read_error threshold [cur %d:max %d]\n",
>> +                         mdname(mddev), rdev->bdev, read_errors, max_read_errors);
>> +               pr_notice("md:%s: %pg: Failing raid device\n",
>> +                         mdname(mddev), rdev->bdev);
> 
> This changed the print message from "md/raid10:" to "md:". We should
> try to avoid
> such changes. How about we do something like the following?
> 
> Thanks,
> Song
> 
> diff --git i/drivers/md/raid1-10.c w/drivers/md/raid1-10.c
> index 3f22edec70e7..6c0ef0fe6ba7 100644
> --- i/drivers/md/raid1-10.c
> +++ w/drivers/md/raid1-10.c
> @@ -173,3 +173,10 @@ static inline void
> raid1_prepare_flush_writes(struct bitmap *bitmap)
>          else
>                  md_bitmap_unplug(bitmap);
>   }
> +
> +static inline bool exceed_read_errors(struct mddev *mddev, struct
> md_rdev *rdev)
> +{
> +       pr_notice("md/" RAID_1_10_NAME ":%s: %pg: Raid device ...\n",
> +                 ...);
> +       ...
> +}
> diff --git i/drivers/md/raid1.c w/drivers/md/raid1.c
> index 9348f1709512..412e98d02a05 100644
> --- i/drivers/md/raid1.c
> +++ w/drivers/md/raid1.c
> @@ -49,6 +49,7 @@ static void lower_barrier(struct r1conf *conf,
> sector_t sector_nr);
>   #define raid1_log(md, fmt, args...)                            \
>          do { if ((md)->queue) blk_add_trace_msg((md)->queue, "raid1 "
> fmt, ##args); } while (0)
> 
> +#define RAID_1_10_NAME "raid1"
>   #include "raid1-10.c"
> 
>   #define START(node) ((node)->start)
> diff --git i/drivers/md/raid10.c w/drivers/md/raid10.c
> index 375c11d6159f..a1531b5f15e3 100644
> --- i/drivers/md/raid10.c
> +++ w/drivers/md/raid10.c
> @@ -77,6 +77,8 @@ static void end_reshape(struct r10conf *conf);
>   #define raid10_log(md, fmt, args...)                           \
>          do { if ((md)->queue) blk_add_trace_msg((md)->queue, "raid10 "
> fmt, ##args); } while (0)
> 
> +#define RAID_1_10_NAME "raid10"
> +
>   #include "raid1-10.c"
> 
>   #define NULL_CMD
> 
> [...]
> 
> .

I agree. Let me improve this in v2.
diff mbox series

Patch

diff --git a/drivers/md/raid1-10.c b/drivers/md/raid1-10.c
index 3f22edec70e7..9e17eab915f5 100644
--- a/drivers/md/raid1-10.c
+++ b/drivers/md/raid1-10.c
@@ -173,3 +173,57 @@  static inline void raid1_prepare_flush_writes(struct bitmap *bitmap)
 	else
 		md_bitmap_unplug(bitmap);
 }
+
+/*
+ * Used by fix_read_error() to decay the per rdev read_errors.
+ * We halve the read error count for every hour that has elapsed
+ * since the last recorded read error.
+ */
+static inline void check_decay_read_errors(struct mddev *mddev, struct md_rdev *rdev)
+{
+	long cur_time_mon;
+	unsigned long hours_since_last;
+	unsigned int read_errors = atomic_read(&rdev->read_errors);
+
+	cur_time_mon = ktime_get_seconds();
+
+	if (rdev->last_read_error == 0) {
+		/* first time we've seen a read error */
+		rdev->last_read_error = cur_time_mon;
+		return;
+	}
+
+	hours_since_last = (long)(cur_time_mon -
+			    rdev->last_read_error) / 3600;
+
+	rdev->last_read_error = cur_time_mon;
+
+	/*
+	 * if hours_since_last is > the number of bits in read_errors
+	 * just set read errors to 0. We do this to avoid
+	 * overflowing the shift of read_errors by hours_since_last.
+	 */
+	if (hours_since_last >= 8 * sizeof(read_errors))
+		atomic_set(&rdev->read_errors, 0);
+	else
+		atomic_set(&rdev->read_errors, read_errors >> hours_since_last);
+}
+
+static inline bool exceed_read_errors(struct mddev *mddev, struct md_rdev *rdev)
+{
+	int max_read_errors = atomic_read(&mddev->max_corr_read_errors);
+	int read_errors;
+
+	check_decay_read_errors(mddev, rdev);
+	read_errors =  atomic_inc_return(&rdev->read_errors);
+	if (read_errors > max_read_errors) {
+		pr_notice("md:%s: %pg: Raid device exceeded read_error threshold [cur %d:max %d]\n",
+			  mdname(mddev), rdev->bdev, read_errors, max_read_errors);
+		pr_notice("md:%s: %pg: Failing raid device\n",
+			  mdname(mddev), rdev->bdev);
+		md_error(mddev, rdev);
+		return true;
+	}
+
+	return false;
+}
diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c
index 375c11d6159f..8ea4974fb91c 100644
--- a/drivers/md/raid10.c
+++ b/drivers/md/raid10.c
@@ -2592,42 +2592,6 @@  static void recovery_request_write(struct mddev *mddev, struct r10bio *r10_bio)
 	}
 }
 
-/*
- * Used by fix_read_error() to decay the per rdev read_errors.
- * We halve the read error count for every hour that has elapsed
- * since the last recorded read error.
- *
- */
-static void check_decay_read_errors(struct mddev *mddev, struct md_rdev *rdev)
-{
-	long cur_time_mon;
-	unsigned long hours_since_last;
-	unsigned int read_errors = atomic_read(&rdev->read_errors);
-
-	cur_time_mon = ktime_get_seconds();
-
-	if (rdev->last_read_error == 0) {
-		/* first time we've seen a read error */
-		rdev->last_read_error = cur_time_mon;
-		return;
-	}
-
-	hours_since_last = (long)(cur_time_mon -
-			    rdev->last_read_error) / 3600;
-
-	rdev->last_read_error = cur_time_mon;
-
-	/*
-	 * if hours_since_last is > the number of bits in read_errors
-	 * just set read errors to 0. We do this to avoid
-	 * overflowing the shift of read_errors by hours_since_last.
-	 */
-	if (hours_since_last >= 8 * sizeof(read_errors))
-		atomic_set(&rdev->read_errors, 0);
-	else
-		atomic_set(&rdev->read_errors, read_errors >> hours_since_last);
-}
-
 static int r10_sync_page_io(struct md_rdev *rdev, sector_t sector,
 			    int sectors, struct page *page, enum req_op op)
 {
@@ -2665,7 +2629,6 @@  static void fix_read_error(struct r10conf *conf, struct mddev *mddev, struct r10
 	int sect = 0; /* Offset from r10_bio->sector */
 	int sectors = r10_bio->sectors, slot = r10_bio->read_slot;
 	struct md_rdev *rdev;
-	int max_read_errors = atomic_read(&mddev->max_corr_read_errors);
 	int d = r10_bio->devs[slot].devnum;
 
 	/* still own a reference to this rdev, so it cannot
@@ -2678,15 +2641,7 @@  static void fix_read_error(struct r10conf *conf, struct mddev *mddev, struct r10
 		   more fix_read_error() attempts */
 		return;
 
-	check_decay_read_errors(mddev, rdev);
-	atomic_inc(&rdev->read_errors);
-	if (atomic_read(&rdev->read_errors) > max_read_errors) {
-		pr_notice("md/raid10:%s: %pg: Raid device exceeded read_error threshold [cur %d:max %d]\n",
-			  mdname(mddev), rdev->bdev,
-			  atomic_read(&rdev->read_errors), max_read_errors);
-		pr_notice("md/raid10:%s: %pg: Failing raid device\n",
-			  mdname(mddev), rdev->bdev);
-		md_error(mddev, rdev);
+	if (exceed_read_errors(mddev, rdev)) {
 		r10_bio->devs[slot].bio = IO_BLOCKED;
 		return;
 	}